A New Zealand startup has developed a way to safely and wirelessly transmit electricity over long distances without the use of copper wires, and is working with the country's second largest electricity distributor to implement it. The dream of wireless power transmission is far from new; everyone's most revered electrical genius, Nikola Tesla, proved in the 1890s that he could power a light bulb two miles away with a 140-foot-long Tesla coil, even though he burned out the generator at the local power plant in doing so, leaving the entire town of Colorado Springs in a blackout.
Tesla's dream is to place giant towers around the world that can wirelessly transmit electricity to any point on the globe, powering homes, businesses, industries, and even giant electric ships on the ocean. Investor J.P. Morgan killed that idea with the famous question, "Where do I put the meter then?"
It's 120 years later, but it seems that New Zealand company Emrod has finally convinced a major electricity distributor to go wireless with its power transmission. Powerco, New Zealand's second-largest electricity distributor, is investing in Emrod, whose technology appears to be able to more efficiently transfer large amounts of power between any two points that can be connected with relays.
Emrod has now made a working prototype device, and will also build another prototype for Powerco, which it plans to deliver by October, then spend a few months testing it in the lab before finally moving to field trials. The prototype device will be capable of delivering "just a few kilowatts" of power, but could easily be scaled up." 'We can transmit 100 times the power over a much longer distance using the exact same technology,' said Emrod founder and serial entrepreneur Greg Kushnir." And, a wireless system using Emrod's technology can transmit any power that current wired solutions transmit."
The system uses a transmitting antenna, a series of relays, and a receiving rectifier antenna (a rectifier antenna capable of converting microwave energy into electrical energy), and each of these components simply appears on a utility pole, looking like a large square. Its beam uses the non-ionizing industrial, scientific, and medical bands of the radio spectrum, including frequencies commonly used in Wi-Fi and Bluetooth.
Unlike Tesla's dream of free power for the whole world, this method allows power to be transmitted directly between specific points with no radiation around it, and a "low-power laser safety curtain" shuts down power transmission immediately before any object such as birds, drones, power thieves, or helicopters can come into contact with the main beam, so there's much more flexibility in where to place the instruments.
Emrod says it can also operate in any atmospheric conditions, including rain, fog, and dust, and the transmission distance is limited only by line-of-sight between each repeater, giving it the potential to transmit power over thousands of kilometers with minimal infrastructure costs, maintenance costs, and environmental impact of a wired solution.
Emrod sees wireless transmission as a key technology for renewable energy generation, which is often done far from where it is needed. Such a system would work well for feeding offshore and remote renewable power generation products into city grids without the need for huge batteries. It also comes in handy during certain unplanned power outages; a truck can be fitted with a rectangular antenna, which can then be driven anywhere within visual range of the repeater to create a temporary wireless power connection.
The company communicated with the New Zealand Radio Spectrum Authority throughout the development process, with a view to meeting all safety standards even when the technology reached high power levels, a process that Kushnir said also helped Emrod develop guidelines for companies that would use the technology.